Chris Fleet describes the role crowdwourcing can play in providing accurate georeferencing for historic map collections online. Presented at the 6th annual Metadata & Web 2.0 seminar organised by the Cataloguing and Indexing Group in Scotland, held at the National Library of Scotland, 21 June 2013

1. Crowdsourced georeferencing for Map Library Collections
Chris Fleet, Senior Map Curator, National Library of Scotland
CIGS Metadata & Web 2.0 Seminar, 21 June 2013

2. 1. Advantages of georeferencing maps for libraries
2. Review of other approaches for crowdsourced georeferencing
3. Georeferencer application in NLS and BL
4. Key success factors
5. Future developments
Crowdsourced georeferencing for Map Library Collections

3. Georeferencing workflow

4. Why georeference maps?
1. To visualise maps in new or better ways
2. To improve access to and retrieval of maps
3. To allow new ways of understanding the content of early maps
4. To allow maps to be integrated with other spatial information
5. To allow maps to be compared more easily to each other

5. 1. To visualise maps in new or better ways

6. 1. To visualise maps in new or better ways

7. 1. To visualise maps in new or better ways

8. 1. To visualise maps in new or better ways

9. 1. To visualise maps in new or better ways

10. 1. To visualise maps in new or better ways

11. 1. To visualise maps in new or better ways

12. 2. To improve access to and retrieval of maps

13. 2. To improve access to and retrieval of maps

14. 2. To improve access to and retrieval of maps

15. 2. To improve access to and retrieval of maps

16. 2. To improve access to and retrieval of maps

17. Map Images viewer

18. 2. NLS OS 25 inch sheet boundaries in ScotlandsPlaces

19. 2. NLS map sheet boundaries in OldMapsOnline

20. eg. Geo-referencing for
understanding the
content of early portolan
charts
3. To allow new ways of understanding the content of early maps

21. 4. To allow maps to be integrated with other spatial information
eg. height – walled city of
Beirut from 18th
century

22. 4. To allow maps to be integrated with other spatial information
eg. property ownership

23. 5. To allow maps to be compared more easily to each other
Online versions at:
digital.nls.uk/bartholomew

24. Other approaches – QUAD-G
http://www.geography.wisc.edu/research/projects/quad-g/

25. Other approaches: NYPL Map Warper
http://maps.nypl.org/warper/

26. Other approaches: eHarta
http://earth.unibuc.ro/articole/eHarta?lang=en

27. NLS Georeferencer – projects page
http://maps.nls.uk/projects/georeferencer/

28. NLS Georeferencer – crowdsourced georeferencing

29. NLS Georeferencer – Georeferencer window

30. NLS Georeferencer – Georeferencer window

31. NLS Georeferencer – Georeferencer window

32. NLS Georeferencer – Visualise window

33. NLS Georeferencer – Accuracy window

34. NLS Georeferencer – Control Points in Google fusion table

35. Georeferenced metadata – MARC extents and GeoTIFF header info
Paris, France
E 2°13'27"-E 2°28'11"/N 48°54'07"-N 48°48'56"
Format for MARC Aleph
034: $$dE0021327$$eE0022811$$fN0485407$$gN0484856
255: $$cE 2°13'27"-E 2°28'11"/N 48°54'07"-N 48°48'56"
Driver: GTiff/GeoTIFF
Files: 100741793.tif
Size is 10642, 8892
Coordinate System is:
PROJCS["OSGB_1936_British_National_Grid",
GEOGCS["GCS_OSGB 1936",
…
Origin = (453544.409153918500000,145329.490622364830000)
Pixel Size = (0.636277533843237,-0.636277533843237)
Metadata:
Corner Coordinates:
Upper Left ( 453544.409, 145329.491) ( 1d14'0.54"W, 51d12'14.93"N)
Lower Left ( 453544.409, 139671.711) ( 1d14'3.57"W, 51d 9'11.77"N)
…

36. NLS Georeferencer - results
1,000 early maps of Scotland - released November 2010
 half of the maps were georeferenced in the first 16 months,
 some categories of maps, such as town plans, completely
georeferenced in this time
But...
 problems with the registration and login
 problems with map image display
 passive promotion
2011 developments
 improved design and professional instructional video
 simpler registration and user logging
 statistics and visualisation tools supporting competition in
crowdsourcing

37. BL Georeferencer – Georeference window

38. BL Georeferencer – Visualise window

39. BL Georeferencer – Visualise window

40. BL Georeferencer – Feb 2012 results: “Round One”
• 725 maps assigned spatial metadata
• Completed in less than one week
• Publicity minimal – social media *key*
• ~90 participants
• Top five completed half the work
• Data quality good: <3% had errors >.005

41. Content relevant
Accessibility and convenience of application
Activity engaging
Immediate results and feedback
Competitive crowdsourcing tools
Recognition and visible overall contribution
Asking the
top five contributors
BL Georeferencer – What made it work ?

42. BL Georeferencer – top georeferencers

43. 44
BL Georeferencer – Competitive widgets

44. ICC Georeferencer – top contributors’ widgets

45. Georeferencer: Future Developments
Adopt personalisation and localisation tools, including a "My Maps"
option, the ability to upload custom scans by individuals, and the
translation of the web interface into other European languages
beyond English.
Include better georeferencing options
Add better support for multi-sheet maps and map series.
Implement WMS / WMTS services - for georeferenced maps, allowing
their presentation in a browser without requiring a Google Earth
browser plugin, as well as in other web-mapping applications.
Allow annotations of georeferenced maps by users and so exploiting
the advantages of semantic links and extraction of textual content
(including place names) from the maps themselves.

46. Crowdsourcing Placenames: Wales1900Cymru Zooniverse Project
http://www.cymru1900wales.org/

47. Thank you
NLS Georeferencer: http://maps.nls.uk/projects/georeferencer/
Fleet, Kowal & Pridal, “Georeferencer: Crowdsourced
Georeferencing for Map Library Collections”,
D-Lib Magazine 18(11/12), November/December 2012
http://www.dlib.org/dlib/november12/fleet/11fleet.html